Lapping machine



March 10. 1925. 7 1,529,141

H. L. NICHOLSON LAPPING MACHINE Filed May 2, 1924 2 Sheets-Sheet 1 INVENTOR March 10, 1925. Y I

I H. L. NICHOLSON LAPPING MACHINE Filed May 2, 1934 2 Sheets-Sheet 2 INVENTOR Patented Mar. 10, 1925.

HARRY L. NICHOLSON, OF WILMERDING, PENNSYLVANIA.

LAPPING MACHINE,

Application filed May 2,

To all whom it may concern:

Be it known that I, HARRY L. NICHOLSON, a citizen of the United States, and a resident of l/Vilmerding, in the county of Allegheny and State of Pennsylvania, have made a new and useful invention in Improvements in a Lapping Machine, of which the following is a specification.

The invention relates to lapping. machines. The machine is particularly designed for lapping piston rings in order tobring them to a definite thickness with their opposing surfaces in parallelism, but the machine may be used for" lapping other articles, if desired. The invention has for its principal object the provision of an improved form of multiple machine of very simple, compact construction, designed to handle a large amount of work with a minimum amount of attention-upon the part of the operator, so that he may attend to a number of other machines-at the same time. Further objects are the provision of improved means for supporting the opposing lapping plates constituting the several units making up the machine, so that they may be readily assembled and disassembled to permit of the rapid removal of: the finishedblanks and their replacement by unfinished ones, and the provision of improved-timing means whereby the operation of each' unit may be automatically stopped after the expiration of a predetermined lapping period, thus insuring uniformity in the lapping 61: feet secured on the product,- and adding to the efliciency of the operator, who is thus relieved of the duty of stopping the units.

when the lapping operation upon each set of blanks is completed.

In practice, the series of sets of lapping plates, driven from a common shaft'and motor are arranged in series onefabove the other upon a vertical standard, with the drive motor at the top of the standard, where it is exposed to a minimum amount of dust resulting from the abrasive action in the lapping operation, but it will be understood that the invention is not limited to this particular vertical arrangement, as

the units constituting the machine, might be arranged in a horizontal series, andth'e pressure for the lapping operation secured by means other than the gravity arrangement incident to thepreferred vertical ar rangement. One embodiment of'the inven- 1924. Serial No; 710,489.

tion is illustratedinthe accompanyingdrawf' ings whereinz, v

Figure l is a side elevation of the'comr plete machine with the upper'portion-thereofpartlyinsection; Fig. 2 is a section on. theline II-I'I of; Fig.1 Figs. 3-and- 4% are enlarged detail-views,-Fig tbeingaisideaelevation of the securing; bolt-for the lappingplates and'Fig.-,3' being a fragmentary side; elevation of; the lapping plates with thebolt in position of use. Fig. 5 is an em: larged vertical section through: the upper portion of one of the lapping;11nits,- and: Fig. 6 is-apartial side elevationiview on an enlarged scale.

As illustrated, the machine comprises three lapping units 1, 2, 3 arranged one above the other, but this number may'be variedor increased asdesired. The units are supported; upon a hollow vertical standard 4, which has itsilower end seated in a heavy base 5. At the topof the standard is a. cap, member or bracket 6, upon Which ismounted the motor 7, by means of which the lapping units'are operated; Projecting All the crank end 1 L This crankend-has a T I slot 15 for a'dj-ustably carrying the crank pin- 16. The-pin is threaded into the nut 17 and carries at its lower end the roller 18. This nut 17 is T shape in cross section tofit the T slot-15, and by looseningthe pin in the nut, the pinmay be adjusted in thecrank arm to vary its-throw.

The crank shafts 12 are all driven from a vertical drive shaft 19 extending longitudnally of thestandard-t, and provided? with the clutch members 20yfree' to rotate upon the shaft. The" members-'20" haveformed integrally therewith suitable 2 sprock-' et wheels which are connected. to' the sprocket wheels 13 ,by' means of the: chains" 21. Splinedto the shaft are other clutch".

members 22 adapted, when in their lower positions, to engage and rotate the members 20. The shaft 19 is driven from the motor 7 through the intermediary of the gears 23 and 23. I 7

As indicated in Fig. 5, the articles to be lapped are the piston rings 24, carried loosely in perforations in the sheet metal carrier plate 25. This plate has riveted at its center the wear ring 26, through which the'crank pin .16 projects. Mounted above and below the carrier plate are the metal lapping plates 27 and 28, having on their opposlng faces, the annular abrasive fabrics 29vand 30. The plates are held against rotation, as hereafter explained, and the rotation of the crank serves to give the carrier'plate a movement of translation with respect to such axis, the piston rings being carried back and forth across the faces of the abrasive strips, so that in one extreme of movement, they occupy the position shown at the right hand side of the plate (Fig. 5) and in their other extreme of movement, they occupy the position shown at the left hand side of the plate.

The upper lapping plates 27 are hung from the arms 8, 9 and 10 as indicated in Figs. 1 and 3. These arms are each provided with a pair of laterally extending Y perforated lugs 32, through which extend the bolts 33, provided at its upper ends with the nuts 34. These bolts also extend loosely through lugs 35 projecting from the sides of the plate 27, collars 36 being provided on the bolts, which act as stops and serve to carry the weight of the plate 27, when such plate is in its lowermost position. The extreme lower ends of the bolts extend loosely through a second pair of lugs 37 projecting laterally from the sides of the lower lapping plate 28. The bolts 33 thus act as guides for the two plates in their up and down movements and prevent their rotation,

and also serve the further function of supporting the upper plate from above when the lower plate is removed to take out the carrier plate as hereafter described.

Mounted beneath the fixed arms 8, 9 and 10, which carry the upper lapping plates 27, as above described, are the swinging arms 38, 39, and 40 which support the lower lapping plates 28. These arms pivot around the standard 4, and are supported by'suitable snap rings 41 mounted in grooves cut in the standard. The ends of the arms are perforated vertically, and carry the platens 42 having the stems 43 (Fig.5) extending down through the perforations. The walls of the arms surrounding the perforations are provided with the inclined cam grooves 44, through which extend the inner ends of the levers 45, such ends being screwed into the stems 43 of the platens. When the levers-Lars swung laterally in one direction,

their stems co-act with the cam grooves to raise the platens, and when they are swung in the opposite direction, the platens are lowered. The lower lapping plates 28 are mounted for free lateral movement on the tops of the platens, and when the levers 45 are swung to one extreme of movement to lower the plates, such plates, together with the carrier plates 25, are moved to a level below the ends of the crank pins 16, and the guide lugs 37 are brought below the ends of the guide bolts-32 so that such plates can be slid off laterally from the platensj plate is removed with the carrier plate, the

upper plate is left suspended in position by the bolts.

When a lapping operation is to be started upon one of the units, a lapping plate 28 is placed upon the platen 42 with a carrier plate thereon carrying the rings to be vlapped, after which the arm is swung to operative position with'the lower lapping plate directly beneath the upper one. The lever 45 is then swung laterally to cam the platen and plate upwardly to the position rier plate is rotated by the crank pin 16.

The bolts 33 fit loosely in'the lugs 35 and 37, so that the two plates can adjust themselves into parallelism and give a properly distributed abrading action to the rings throughout the lapping operation.

In order to facilitate the work of the operator, a timing device is applied to each unit of the machine. These units operate independently, but are identical in construction, so that a detailed description of one device only is necessary. The devices are all operated from a vertical timing shaft 46, mounted in suitable bearings on the standard 4 and driven from the shaft 19 through the gears 47 and'48 carried respectively by the shafts 19 and 46. Projecting laterally from the standard 4 are the three casings 49, carrying thetransverse shafts 50 to which worm wheels 51 are keyed. These worm wheels are driven by worms carried by the shaft 46. Keyed or pinned to the shafts 50 at the front of the casings are the perforated discs 54:. The extreme outer ends of the shafts carry the arms 55, which are loose on the shafts and free to rotate with respect'thereto. The outer ends of the arms carry spring pressed pins 56 adapted to engage any one of the perforations in the discs 54, so that the arms may belocked to the discs (in various positions of rotary adjustment) so as to rotate therewith. The ends of the arms are also provided with operating lugs 57 for operating theclutch devices as will now be described. The clutch members 22 are each operated by a yoke 58, carried by a horizontal shaft 59 journalled in the standard 4. and having at its outer end a counterweighted lever arm 60, which is held in horizontal position (with the member 22 in engagement with the member 20) by means of the retainer 61 pivoted at 62 (Fig. 6). lVhen the retainer is swung to the right to the position A, indicated in dotted lines in Fig. 6, the arm swings downwardly by gratu ty, rotating the shaft 59 and moving the clutch member 22 upward, thus interrupting the drive of the member 20 and stopping the rotation of the carrier plate of the lapping unit. The movement of the armKSO is alsoarranged so as to disconnect the drive of the timing mechanism. This is accomplished by the use of clutches 53 on the shaft 46, similar to the clutches 20, 22, with the upper member splined to the shaft and releasable by an upward movement. This upper clutch member is connected to the yoke 64 on the inner end of the arm 60. The downward movement to the arm 60 thus unclutches the clutch 53 simultaneously with the unclutching of the clutch 20, 22, so that the timing mechanism is stopped when the lapping unit is stopped. The retainer 61 is automatically released (as above described) by the lug 57 which engages a laterally projecting lug 65 when the arm 55 is rotated to such anextent as to cause an interengagement between the lugs and a camming' of the retainer to the right.

The length of time which a lapping'unit should operate in order to secure a certain lapping e'fiect is determined by trial, after which, the arms 55 are each set at a position of rotary adjustment such as to permit the expiration of such period of time before the retainers are engaged by the lugs on the arms and swung to release position. The operator is thus relieved of the duty of stopping the units, which enables him to attend to a greater number of: machines than would otherwisebe the case, and adefinite and uniform lapping effect on .each set of articles is insured. The operator can also apply the carrier plates with the articles to be lapped therein to each unit independently of the others and immediately start it while the others are operating, so that the loss of time incident to the recharging of themachine at any one time is limited to a single unit. The gearing which secures the rotation of the perforated disc 54 (and with it the arm 55) has a degree of reduction such that the period required for lapping any set of articles is less than that required for a complete revolution of the disc, and since the timing mechanism is unclutched when the lapping operation is terminated, the resetting of the arm 57 with respect to the'disc 55 is more readily accomplished than if the connection of the mechanism to the drive shaft were continuous.

lVhat I claims is:

1. In combination in a lappingn'iachine, a series of pairs of lapping plates having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between each pair of'lapping plates, crank means for giving each of the carrier plates a movement of rotation and translation laterally with respect to the lapping plates, a standard extending longitudinally of the series of lapping plates,'independent supporting means 011 the standard for each of said plates arranged so that-one member of each pair of plates may be swung laterally to bring it out of alignment with the other member of each pair, ajdri-v'e shaft mounted in the standard and extending longitudinally thereof, and driving connections between such shaft and each of said crank means. v

2. In combination ina lapping machine, aseries of pairs of lapping plates having opposing abrading surfaces, a" carrier plate having perforations for the articles to be lapped lying between each pair of lapping plates, crank means for iving each of the carrier plate-s a movement of rotation and translation laterally with respect to the lap ping plates, a standard extendin longitudinally of the series of lapping plates, independent supporting means on thestandard for each of said'plates arranged so that one member of each pair of plates may he swunglaterally to bring it out of alignment with the other member of each pair, and also moved longitudinally of the standard, a drive shaft, extending longitudinally of the series of lapping plates, and driving connections between such shaft and each of said crank means.

p 3. In combination in a lanning machine a series of pairs of lapping lates arranged in vertical alignment one above the other and having opposingab-rading surfaces, a

carrier plate having perforations for the articles to be lapped lying between each pair of lapping plates, crank means for giving each of the carrier plates a movement of rotation and translation lat-erally with "respect to the lapping plates, a standard extending longitudinally of the series of lapping plates and supporting said plates, a motor mounted on the standard above the lapping plates, a drive shaft extending longitudinally of the standardand driven from said motor and driving connections between said shaft and each of said crank means.

4. In combination in a lapping machine, aseries of pairs of lapping plates arranged in vertical alignment one above the other and having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between each pair of lapping plates, crank means for giving each of the carrier plates a movement of rotation and translation laterally with respect to the lapping plates, a standard extending longitudinally of the series of lapping plates and supporting said plates, independent supporting means on the standard for each of said plates arranged so that one member of each pair of plates may be swung laterally to bring it out of alignment with the other member of each pair, a drive shaft mounted in the standard, and driving connections be tween said shaft and each of said crank means.

5. In combination in a lapping machine, a series of pairs of lapping plates arranged in vertical alignment one above the other and having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between each pair of lapping plates, crank means for giving each of the carrier plates a movement of rotation and translation laterally'with respect to the lapping plates, a standard extending longitudinally of the series of lapping plates and supporting said plates, independent supporting means on the standard for each of said plates arranged so that the lower member of each pair of plates may be swung laterally to bring it out of alignment with the other member of each pair and also moved longitudinally of the standard, a drive shaft mounted in the standard, and driving connections between said shaft and said crank means.

6. In combination in a lapping machine, a series of pairs of lapping plates having opposing abrading surfaces, a carrier plate havin perforations for the articles to be lapped lying between each pair of lapping plates, crank means for giving each of the carrier plates a movement of rotation and l t on laterally with respect to the lapping plates, a standard extending longitudinally of the series of lapping plates, independent supporting means on the standard for each of said plates arranged so that one member of each pair of plates may be swung laterally to bring it out of alignment with the other member of each pair, a drive shaft mounted in the standard and extending longitudinally thereof, an independent releasable driving connection between such shaft and each of said crank means, and a timing device for each of said carrier plates adapted to auto matically release each of said driving connections at the end of a predetermined lapping period for which each of the devices may be set.

7. In combination in a lapping machine, a series of pairs of lapping plates having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between each pair of lapping plates, crank means for giving each of the carrier plates a movement of rotation and translation laterally with respect to the lapping plates, a standard extending longitudinally of the series of lapping plates, independent supporting means on the standard for each of said plates arranged so that one member of each pair of plates may be swung laterally to bring it out of alignment with'the other member of each pair, a drive shaft mounted in the standard and extending 1ongitudinally thereof, an independent releasable driving connection between such shaft and each of said crank means, a timing shaft also extending longitudinally of the standard, a motor carried by the standard in driving relation to both of said shafts, a timing 10o device for each of said carrier plates, a releasable connection between said timing shaft and each of said timing devices, and means operated by each of the timing devices for releasing the connection between the may drive shaft and one of the crank means and between the timing shaft and the corresponding timing device after the expiration of a predetermined lapping period for which the timing device may be set.

8. In combination in a lapping machine, a pair of annular lapping plates arranged one above the other and having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped 115 lying between the plates, crank means projecting down through the upper lappingplate for giving the carrier plate a movement of rotation'and translation laterally with respect to the lapping plates, means 12 for driving the crank means, a platen supporting the lower lapping plate so as to permit relative lateral movement thereof, means for moving the platen vertically, and guide means for the lapping plates prevent- 125 ing rotary movement thereof, but permitting free vertical movement.

9. In combination in a lapping machine, a pair of annular lapping plates arranged one above the other and having opposing 1 abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between the plates, crank means pro jecting down through the upper lapping plate for giving the carrier plate a movement of rotation and translation laterally with respect to the lapping plates, means for driving the crank means, a platen supporting the lower lapping plate and mounted on an axis of rotation to one side of the lapping plates so that the platen may be swung out from beneath the lapping plates, means for moving the platen vertically, and guide means for the lapping plates preventing rotary movement thereof, but permitting free vertical movement.

10. In combination in a lapping machine, a pair of annular lapping plates arranged one above the other and having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between the plates, crank means projecting down through the upper lapping plate for giving the carrier plate a movement of rotation and translation laterally with respect to the lapping plates, means for driving the crank means, a platen supporting the lower lapping plate so as to permit relative lateral movement thereof, means for moving the platen vertically, guide means for the lapping plates preventing rotary movement thereof, but permitting free vertical movement thereof, and stop means for limiting the downward movement of the upper lapping plate, so that it is supported by such means when the platen and the lower lapping plate are moved downward for the removal of such lower lapping plate and the carrier plate supported thereon.

11. In combination in a lapping machine, a pair of annular lapping plates arranged one above the other and having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between the plates, crank means projecting down through the upper lapping plate for giving the carrier plate a movement of rotation and translation laterally with respect to the lapping plates, means for driving the crank means, a platen supporting the lower lapping plate and mounted 011 an axis of rotation to one side of the lapping plates so that the platen may be swung out from beneath the lapping plates, means for moving the platen vertically, guide means for both lapping plates supported from above arranged so as to prevent rotary movement of the plates but permitting free vertical movement thereof, and stop means carried by said guide means for limiting the downward movement of the upper lapping plate, so that it is supported by the guide means when the platen is lowered and swung laterally.

12. In combination in a lapping machine, an upright standard provided with' a laterally extending arm, a pair of annular lapping plates beneath such arm arranged one above the other, and having opposing abrading surfaces, a carrier plate having perforations for the articles to be lapped lying between the plates, crank means carried by said arm and projecting down through the upper lapping plate for giving the carrier plate a movement of rotation and translation laterally with respect to the lapping plates, means for driving the crank means, a second arm mounted on the standard below the lapping plates, and adapted to swing laterally, a platen mounted for vertical movement on the end of said second arm and supporting the lower lapping plate so that such plate may be removed laterally therefrom, guide means for both lapping plates carried by said first arm and arranged to permit free vertical movement of such plates, but prevent rotary movement thereof, and stop means for limiting the downward movement of the upper lapping plate, so that it is supported by such means when the platen is lowered and the arm carrying the platen and lower lapping plate are swung laterally from beneath the upper lapping plate.

In testimony whereof, I have hereunto subscribed my name this 29th day of April, 1924. 1

HARRY L. NICHOLSON. 

